Statistical methods and theory impinge on cancer research in almost all its aspects. Those aspects include diverse laboratory investigations, cancer epidemiology, clinical trials, experimental cancer chemotherapy, carcinogenesis testing, identification of environmental carcinogens, etc. Certain of these have common statistical features. Thus, the possibility of many variables having influential effects arises in prospective and retrospective epidemiological investigations as well as in clinical investigations, necessitating the application of multivariate statistical methods. The time-to-response nature of observation arises variously in prospective epidemiological studies, in clinical trials, and in carcinogenesis assays, this requiring particular approaches for statistical analysis. The need for yet other statistical techniques arises in particular cancer investigations as, for example, the identification of disease clustering. Of emerging and signal importance is the role that statitics can play in establishing safe levels for potential carcinogens which man may be introducing into his environment. The objective of the proposed research is to identify important statistical needs in cancer research and to try to fill them.